Why is RIA services known as black magic? - wcf-ria-services

Question

Why do people call RIA services a black magic? What kind of black magic do they refer to ? Also, i have seen most people do not use RIA even though they are in Silverlight world. Why is it so? Even on stackoverflow, the % of people asking as well as answering to RIA services question is very very low. Why is it so?

Answer 1

WCF RIA Services provides the following benefits:
Makes a WCF RIA service that supports IQueryable and IEnumerable; WCF RIA Services creates client-side proxy which allows you to send only expression trees over the wire from the client in order to get back just the data you need. For example: you can call a method in your ria service called GetProducts() but also add a LINQ lambda such as GetProducts().Where( d => d.Quantity > 50 ) and only the expression is sent over the wire to the server. The server does the filtering and returns just the matches as strongly typed objects.
Dynamic generation of OData, REST/JSON, and SOAP endpoints with little more than a single line per endpoint in your web.Config.
Ability to automatically flow business rules created at the middle tier into the client tier
Allows you to efficiently flow validations from the middle tier to the user
Allows property, parameter, method, object, collection, and changeset level business rules through simple data annotation validator decoration
There are some deficiencies:
Still does not support WS-* (will in 5) for RPC
OData provider is not queryable

Answer 2

Well, I have not yet heard of people referring to WCF RIA Services as black magic.
I believe there is a small number of people using it (compared to the number of people writing stuff in Silverlight), because it is younger. People may have been developing their Silverlight applications for some time now (version 3.0 came out in July 2009) using classic WCF Services.
WCR RIA Services is still new (version 1.0 came out in May 2010, the final SP1 in December 2010) and we all know the rule, "Never change a running system", so if someone already has a working WCF webservice, why change it? In my case, we experimented with Silverlight and WCF some time ago and decided to wait. When RIA Services came out we thought that was great and started working on a Silverlight version of our main application. It is much easier using RIA Services in a new project than chaning your webservice access in an existing one.
In addition to that it should be noted that Silverlight is not limited to business applications with database access using a webservice. Therefore there may be quite a few Silverlight developers who do not need any kind of webservice.
Another reason might be the fact that for web applications requiring a database other technologies like ASP.NET, ASP.NET MVC, even PHP or JSP (and possibly others I may not even have heard of) have existed for quite a while. And although business applications ought to look nice, too, it usually is not the top requirement to have all kinds of fancy graphics and animations, etc.
Finally, why are so few questions regarding RIA Services asked on SO? Well, they do have their own forum which seems to be quite active. (I use it as a resource when looking for answers but don't post there.)

Answer 3

Regarding the "black magic" part of your question, I believe it is the ongoing shift to convention over configuration. Compared to vanilla WCF, you end up writing very little code to build the client-server relationship. Also, the WCF RIA tooling does a substantial amount of code generation to achieve this.
More on convention over configuration on specifically with WCF RIA and generally at Wikipedia.